Development Application - Part 2 of 2 - Report & Plans · OPW11/0116

In the medium term, it could be expected that the river will meander to the south as it has in the past. The training wall and
submerged "closure" become control points for the flow and the channel alignment would be expected to develop similarly to
Figure 38. This is a very natural alignment for the river and should not impact unduly on the long term evolution of the river
or the inclination of the river to meander to either the north or the south. It would be expected to result in increased velocities
and greater depths adjacent to the end of the training wall and along the river side of the curved "closure", but it is expected
that while the performance of the structure may vary slightly, it should continue to mitigate erosion levels, preventing
breaching of the Spit and providing improved amenity. Given the fact that the structures are essentially within the 2002
channel alignment, the potential impact of the works on the river system would be expected to be similar to that experienced
in 2002.




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Figure 38: Likely future channel alignment for Option E, similar to 2002 alignment

The potential impacts of Option D3 include:
               •    Reduced erosion along the length of the Noosa River Spit
               •    Threat of breaching eliminated
               •    No further erosion at end of Noosa River Spit
               •    Possible end effects may result in increases to erosion of mangrove area at end of the Noosa River Spit
                    [presently experiencing high levels of natural erosion]
               •    Erosion further upstream not anticipated
               •    Naturally active sand shoals may be affected
               •    Potential impact on river evolution similar to 2002 conditions

This option should be effective at stabilizing the full length of the Noosa River Spit and creating a calm lagoon area and
recreational beach while also minimizing the impact of the works on the river dynamics.